A269102 Number of n X n 0..3 arrays with some element plus some horizontally or vertically adjacent neighbor totalling three no more than once.

4, 180, 40908, 43964700, 232068730044, 6206909793496236, 858502190008810133292, 622342168717398556687064028, 2386083493285894017930101786679468

Offset: 1

Author

R. H. Hardin, Feb 19 2016

Keywords

• nonn

Comments

Diagonal of A269109.

Examples

			Some solutions for n=3
..0..1..3. .3..1..0. .3..1..3. .0..0..2. .0..2..3. .2..0..1. .0..0..0
..0..2..2. .2..1..0. .2..0..1. .1..2..0. .1..3..3. .0..1..0. .0..1..0
..2..0..2. .2..0..0. .3..3..3. .0..2..2. .1..1..2. .2..0..2. .2..3..3
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..11

Crossrefs

Cf. A269109.